The CBCB issued notices to oil firms, seeking their explanation within 24 hours.

The Central Pollution Control Board Monday sought explanations from various oil companies for their failure in installing "vapour recovery" systems at fuel stations. Vapour recovery device is an instrument to capture displaced vapours that emerge from inside a vehicle's fuel tank while filling petrol or diesel in it.

The CBCB issued notices to oil firms, seeking their explanation within 24 hours.